1. Field of the Invention
The present invention relates generally to retractable awnings and more particularly to a retractable awning that incorporates solar cells for generating electricity from solar radiation.
2. Description of the Prior Art
Retractable awnings have been utilized for many years, particularly as awnings for windows or entry doors of building structures. The awnings are typically rolled out during daylight hours to block undesired sun rays and rolled in at night when the sun has gone down. Such awnings normally include a roll bar which is mounted in a moveable manner along an outer edge of the awning sheet so as to roll away from and back to the building as the awning is extended and retracted, respectively.
More recently, retractable awnings have also been mounted on the sides of mobile homes, recreational vehicles, travel trailers or the like. These newer versions of the retractable awning normally include support posts for supporting the outer edge of the awning sheet either by forming a brace from a side wall of the vehicle or by forming a ground support.
A concern with all retractable awnings relates to deterioration of the awning such as is caused by adverse weather elements or prolonged exposure to the sun. Accordingly, it is not uncommon to provide a strip of weather retardant fabric or rubberized material adjacent the inner edge of the awning sheet so that when the awning sheet is completely rolled into its retracted position, the weather retardant material will surround the remaining portion of the awning sheet thereby protecting the awning sheet from adverse environmental elements and ultraviolet radiation from the sun. Some retractable awnings for recreational vehicles and the like have even been mounted in metallic boxes so that the box can be closed to protect the awning when it is retracted.
A more recent development adapted to protect an awning from environmental elements when the awning is not in use consists of a plurality of elongated slats, usually of aluminum, which are pivotally connected along their length in an articulated manner so as to envelop or encapsulate the awning when it is rolled into its retracted position. The articulated slats are used in lieu of weather retardant fabric materials. One problem with the articulated slats, however, is that the joints between adjacent slats typically are not watertight. Accordingly, rain, water and the like can seep between adjacent slats and leak underneath the awning in an undesired manner.
Systems have been designed to prevent leakage between the slats so that the slat system for protecting the awning sheet is becoming more popular. An example of a system for sealing the joints between adjacent articulated slats is disclosed in U.S. Pat. No. 4,909,296, entitled "Water-Tight Sealing System for Articulated Slats" which is commonly owned with the present application.
Since most recreational vehicles, travel trailers or the like are frequently in remote locations where they cannot be directly connected to a source of electric power, and since there are numerous needs for electricity on such vehicles, it has been commonplace to provide gasoline powered generators for such vehicles. The use of such generators, however, is not totally desirable in that they are noisy and thus disrupting in serene environments where such vehicles are many times taken. If the electrically driven accessory items on the vehicle are powered by battery and are used very extensively, they will run down the battery and accordingly there has been a need for alternative sources of electrical power for such vehicles.
With the recent developments in solar collectors, solar cells and the like, it is known to mount such a collector or cell on the top of a recreational vehicle, travel trailer or the like so that electrical energy can be gathered and stored in a battery any time the sun is shining, but the solar collectors and cells take up valuable space on the top of the vehicle where many times air conditioning units, storage space and the like is provided.
It is against this background that the retractable awning of the present invention has been developed.